Widest rim and tire for full mini tub to frame

What is the widest wheel and tire I can run on a 70 dart GT tubbed all the way to the frame,thanks

whatever the measurement from the outside of the tub to the inside of the frame is, minus a half inch for sidewall flex should be close

Hey I like your username!I am also disabled,but not dead...Just wanted to ask why the full tub? Dont need a back seat I guess...personally Im minitubbing as it retaines the stock look and back seat without modding it.

On my '71 GT there's 12" from the quarter lip to the stock wheel tub, and a little over 2.5" from the wheel tub to the outside of the frame. That distance changes over the length of the wheel tub but that's what it is in the middle near the axle. So, call it 14.5" from quarter lip to frame with a minitub and 3" spring relocation.

You'll need about a 1/2" of clearance on each side to keep the tires from rubbing, so that gives you about 13.5" of space to work with. A 335mm tire has a section width that's 13.5" wide, so I'd say that's about the max. And since the outside to outside width on a rim is an inch wider than the advertised width I'd say a 12" wide rim would be about as much as I would run. i suppose technically a 12.5" wide rim would work but the sidewall would have to be pretty much even with the rim lip for clearance.

And the usual disclaimer that all of these cars are a little different, a 1/4" from one car to another isn't unusual. Heck sometimes they're off by as much as quarter inch from one side to the other on the same car, you have to measure. My measurement also included a stock quarter lip, there's usually a good 1/2" you can gain there by cutting it back. Depending on the quarter lip trimming, ride height, and the particular car a 345 might be possible, that tire has a section width around 14". A 335 should be a fairly safe bet, the 345 would come down to the individual car and it's particular set up.

I know @72BBSwinger has 335's on his 70+ Dart, and I seem to recall him saying he had a little room left on his car.

I just want to make use of all available space if I am going to the trouble of moving the springs in and full mini tub should be the term for what I am doing,ill be using trailer fenders and inner walls for the mini tub so I can still use the back seat and thanks for all the help I appreciate it,i got the trailer fender idea from another member on here there is a thread on it somewhere,i was hoping for 325/50 tires on 12" rims but if I can get 335s by trimming the wheel lip that would be great.ive got my 8 3/4 all set up to narrow so I'll have to get the inner and outer original wheel wells out and trim the lips and get some tires mounted and see what will work and how much I can cut rear and still be ok.

I run 390/40r17 on a 12" wide wheel on my Duster body. Same wheel well set up and you have to option on a Dart to move the tire back and center it in the opening.

Here is some thought. I had a 68 dart. Mini tubbed, springs moved in, 3 inches off each side of the rear housing. Had a 15x10 rims with 325/50/15s Had lots of room on both sides of the tire. Cant remember the back spacing

72 Dart
325/50-15
10" wheel , 5" back space

First off, you need to look at the section with of the tire and what rim that section width was taken from. Don't assume all 325/50 tires are all the same section width because they aren't.

2nd, depending on the size of the tire and where the tire sits in the tub (read that as the cars ride height) the room you have to work with may change

3rd, If you plan on doing anything other than straight line with the car you may want a little more than a 1/2". Your suspension type and stiffness will play some roll in this as well.

I can tell you what I run and it pushes the mimits to the max. They rub at times both on the inside and outside as the tires are perfectly centered in the wheel wells

28x12.50x15 on an 11.25" rim.

roccodart440 said:

First off, you need to look at the section with of the tire and what rim that section width was taken from. Don't assume all 325/50 tires are all the same section width because they aren't.

2nd, depending on the size of the tire and where the tire sits in the tub (read that as the cars ride height) the room you have to work with may change

3rd, If you plan on doing anything other than straight line with the car you may want a little more than a 1/2". Your suspension type and stiffness will play some roll in this as well.

I can tell you what I run and it pushes the mimits to the max. They rub at times both on the inside and outside as the tires are perfectly centered in the wheel wells

28x12.50x15 on an 11.25" rim.

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Nice car, are there any mods done to the rear axle, springs or wheel tubs?

ktcnn94 said:

Nice car, are there any mods done to the rear axle, springs or wheel tubs?

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It's a Dana built by strange and it is narrowed. the wheel wells are mini tubed.

I run 28 x 13.50 x 15s

I have run 325 Hoosiers on my tubbed 72 Scamp, they are listed as 13.1 inches wide. With a 1/2 inch clearance to the springs l could still fit my fingers between the outside of the tire and the fender. So I would say a 335 should work if the stars line up... but not ever car is the same